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Filters: Tags: monitoring 1-Changes in Plant and Animal Distribution: Fauna (X) > partyWithName: Boonstra, Rudy (X) > partyWithName: Krebs, Charles J. (X) > Categories: Publication (X)

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Small mammals in boreal forest ecosystems fluctuate dramatically in abundance and 1 possible mechanism to explain these changes is the bottom-up hypothesis of variation in food supplies. Here we ask if variation in berry crops produced by 6 major species of dwarf shrubs and herbs, epigeous mushroom crops, and white spruce seeds allow us to predict changes in the abundance of the red-backed vole (Myodes [= Clethrionomys] rutilus), the deer mouse (Peromyscus maniculatus), and field voles (Microtus oeconomus and M. pennsylvanicus combined) over 13 years (1997-2009) in the Kluane Lake region of the southwestern Yukon, Canada. M. rutilus is the dominant rodent in these forests, comprising 64% of the catch. Overwinter...
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We review the population dynamics of red-backed voles (Myodes species) in North America, the main deciduous and coniferous forest-dwelling microtines on this continent, and compare and contrast their pattern with that of the same or similar species in Eurasia. We identify 7 long-term studies of population changes in Myodes in North America. Using autoregressive and spectral analysis, we found that only 2 of the 7 show 3- to 5-year cycles like those found in some Eurasian populations. There was no relationship between latitude and cycling. The general lack of cyclicity is associated with two key aspects of their demography that act in tandem: first, poor overwinter survival in most years; second, chronically low...
Estimating population densities of small mammals (< 100 g) has typically been carried out by intensive livetrapping, but this technique may be stressful to animals and the effort required is considerable. Here, we used camera traps to detect small mammal presence and assessed if this provided a feasible alternative to livetrapping for density estimation. During 2010-2012, we used camera trapping in conjunction with mark-recapture livetrapping to estimate the density of northern red-backed voles (Myodes rutilus) and deer mice (Peromyscus maniculatus) in the boreal forest of Yukon, Canada. Densities for these 2 species ranged from 0.29 to 9.21 animals/ha and 0 to 5.90 animals/ha, respectively, over the course of this...
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Predation is a central organizing process affecting populations and communities. Traditionally, ecologists have focused on the direct effects of predation--the killing of prey. However, predators also have significant sublethal effects on prey populations. We investigated how fluctuating predation risk affected the stress physiology of a cyclic population of snowshoe hares (Lepus americanus) in the Yukon, finding that they are extremely sensitive to the fluctuating risk of predation. In years of high predator numbers, hares had greater plasma cortisol levels at capture, greater fecal cortisol metabolite levels, a greater plasma cortisol response to a hormone challenge, a greater ability to mobilize energy and poorer...


map background search result map search result map Do changes in berry crops drive population fluctuations in small rodents in the southwestern Yukon? Density estimation for small mammals from livetrapping grids: rodents in northern Canada From process to pattern: how fluctuating predation risk impacts the stress axis of snowshoe hares during the 10-year cycle Population dynamics of red-backed voles (Myodes) in North America Population limitation of the northern red-backed vole in the boreal forests of northern Canada The Community Ecological Monitoring Program Annual Report 2009 The Community Ecological Monitoring Program Annual Report 2012 Synchrony in the snowshoe hare (Lepus americanus) cycle in northwestern North America, 1970-2012 What factors determine cyclic amplitude in the snowshoe hare (Lepus americanus) cycle? Estimating snowshoe hare population density from pellet plots: a further evaluation The role of red squirrels and arctic ground squirrels Herbivores - Forest grouse and ptarmigan Great Horned Owls Other herbivores and small predators - Arthropods, birds, and mammals Arctic ground squirrel population collapse in the boreal forests of the Southern Yukon Ecosystem Dynamics of the Boreal Forest: the Kluane Project Voles and mice Fear and lethality in snowshoe hares: the deadly effects of non-consumptive predation risk The impact of rewilding, species introductions and climate change on the structure and function of the Yukon boreal forest ecosystem Fear and lethality in snowshoe hares: the deadly effects of non-consumptive predation risk From process to pattern: how fluctuating predation risk impacts the stress axis of snowshoe hares during the 10-year cycle Density estimation for small mammals from livetrapping grids: rodents in northern Canada Herbivores - Forest grouse and ptarmigan Other herbivores and small predators - Arthropods, birds, and mammals The role of red squirrels and arctic ground squirrels Voles and mice Great Horned Owls Arctic ground squirrel population collapse in the boreal forests of the Southern Yukon Do changes in berry crops drive population fluctuations in small rodents in the southwestern Yukon? Estimating snowshoe hare population density from pellet plots: a further evaluation Ecosystem Dynamics of the Boreal Forest: the Kluane Project The Community Ecological Monitoring Program Annual Report 2009 The Community Ecological Monitoring Program Annual Report 2012 The impact of rewilding, species introductions and climate change on the structure and function of the Yukon boreal forest ecosystem Population dynamics of red-backed voles (Myodes) in North America Synchrony in the snowshoe hare (Lepus americanus) cycle in northwestern North America, 1970-2012 What factors determine cyclic amplitude in the snowshoe hare (Lepus americanus) cycle? Population limitation of the northern red-backed vole in the boreal forests of northern Canada